Revolving chair.



No. 635,764. Patented Oct. 3|, I899.

J. M. GERMANSUN.

REVOLVING CHAIR.

(Application filed June 12, 1899.) (No Model.)

E 12' r HZ 6 5 i Nrrn STATES JULIUS M. GERMANSON, OF MILW'AUKEE,WISCONSIN, ASSIGNOR TO THE WESTERN MALLEABLE AND GREY IRON MANUFACTURINGCOMPANY,

OF SAME PLACE.

REVOLVING CHAIR.

SPECIFICATION forming part of Letters Patent N 0. 635,764, dated October31, 1899.

Application filed June 12,1899. Serial No. 720,18 l. (No model.)

To all whom it nuty concern.-

I Be it known that I, JULIUS M. GERMANSON, of Milwaukee, in the countyof Milwaukee and State of \Visconsin, have invented a new and usefulImprovement in Revolving Chairs, of which the following is adescription, reference being had to the accompanyingdrawings, which area part of this specification.

The object of my invention is to provide improved means for adjustingthe seat of achair up and down in connection with'improved means foradapting the chair-seat to rotate freely while adequately supported.Revolving chairs are made and sold in large nu mbers. Any new mode ofconstruction that lessens the cost of production is of great value ifthe new form of construction is as strong and enduring and as reliablein its support and as easily operated as old forms, and if the new formthat can be made at a less expense than the old form has also featuresof excellence relating to steadiness of parts, absence of friction andwear, &c., over the old form, then additional value exists therein. Myimproved construction contains all these points of superiority over oldforms of construction.

The invention consists of the device, its parts and combinations ofparts, as herein described and claimed, or the equivalents thereof.

Figure 1 shows my improved chair iron or device in cross-section aboutcentrally. Fig. 2 is a top plan view of the hub. Fig. 3 is a transversesection of the lower portion of the sleeve. Fig. 4 is a view of thelower end of the screw.

In the drawings, 5 is a chair-hub, preferably made of cast metal andadapted to receive therein the upper ends of the legs of the chair, andthereby hold the legs in position, the hub being adapted to support thechairseat thereon. The hub 5 is provided with a central verticalaperture or bore, the upper portion of which is of larger diameter thanthe lower portion, there being an annular shoulder 6 at the lower end ofthe enlarged upper portion of the bore. A sleeve 7, fitted in the largerupper portion of the bore of the hub 5, rests rotatably on the shoulder6, the sleeve below the shoulder 6 having a less exterior diameter thanthe part above that shoulder. The construction of the sleeve is suchthat the portion above the shoulder 6 is considerably thicker laterallythan the part 7 below the shoulder 6, the aperture through the sleevebeing substantially of the same diameter throughout the length of thesleeve. For providing bearing-surfaces on the sleeve 7 adapted to bearagainst the inner surface of the bore of the hub 5 at localities nearthe top and the bottom of the hub and medially thereof I provide thesmooth annular and somewhat-raised surfaces 8 8, which, being adapted tobear laterally against the hub at different planes in the length thereofvertically, adapts the sleeve to be supported thereby in the hub againstlateral displacement, while at the same time having only such limitedbearin g-surface in contact with the interior of the hub as to reducethe friction to the minimum amount. This sleeve is preferably madeinexpensively of cast-iron and is provided with a longitudinal groove orgrooves 9 9 on its inner surface throughout its length, which groove orgrooves in that portion of the sleeve that is thin and projectsdownwardly below the shoulder 6 may cut through the wall of the sleeve,though it is not necessary that it should do so. The s1eeve7 extendsfrom below the hub to near the top of the hub. A screw 10, which isadapted to support a chairseat fixed thereon, fits loosely in thechamber of the sleeve and is provided with a pin 11, that projectslaterally therefrom at one or both sides and is adapted to enter looselythe groove or grooves 9 and prevent the rotation of the screw in thesleeve, while permitting of the movement of the screw verticallytherein. The screw is made of hard metal, preferably of malleable ironor steel; but the pin 11 is readily inserted therein by first drilling asmall but suitable hole therefor through the pin transversely. A nut 12,provided with a handwheel 13, turns by its thread on the screw 10, andthe nut at its lower extremity rests on the sleeve 7, preferably in anannular recess therefor at the top of the sleeve about the bore thereof.The nut 12 is of less diameter than the bore of the upper part of thehub 5, and the not therefore does not in any place bear against the hub5, either frictionally or otherwise. Near its lower extremity and justabove the sleeve 7 the hub 12 is provided with an annular grooveexteriorly, and a retaining-screw 14, turning through the hub 5, entersthe groove in the nut 12 sufficiently to prevent the removal of the nutfrom its position in the hub when the retaining-screw is in place. Thescrew 10, with its pin 11, can when the parts are being put together bereadily inserted in the sleeve 7 without any special or peculiarconstruction of the lower extremity of the screw,since the screw readilyenters the cham ber of the sleeve and the pin 11 will readily enter thegroove or grooves 9 when brought to position to register therewith.

It will be seen that this construction in which the screw is adapted torotate with the sleeve obviates the necessity of cutting a longitudinalgroove in the screw, as has heretofore in some instances been done,which groove-cutting is very expensive, especially as for cutting thegroove in large numbers of screws a machineis required specially adaptedfor such purpose. Also it will be seen that the groove in the sleeve 7,which can be pro-- duced in molding and casting the sleeve, is aninexpensive process, and also that the boring the screw transversely forthe pin 11 and the inserting the pin in the screw is a simple andinexpensive process, and that as a result of this construction,amongother benefits,the screw is adapted to be readily inserted in the sleevewithout requiring a special preparation or formation of the lowerextremity of the screw, as has been employed in some chain irons of thisgeneral character heretofore.

It will be understood that, in this construction, by rotating the nut 12by means of the hand-wheel 18 the screw 10 and the seat thereon arereadily raised or lowered and that being thus adjusted to a suitableheight the chair-seat, with the screw 10 and with the sleeve 7, is freeto revolve in the hub 5, there being therefor smooth annular bearings atdifferent planes in the hub 5, but so distributed that bearings occurnear the top and near the bottom of the hub, thus preventing unduestrain on inadequate parts or lateral displacement.

YVhat I claim as my invention is 1. The combination with a chair-h ubhaving a smooth vertical bore and a medially-disposed annular shouldertherein, ot a sleeve substantially as long as and fitted and revolublein said hub on said annularshoulder therein, a screw fitted loosely inthe sleeve and held to rotation therewith while movable endwise therein,and a nut turning on said screw and supported revolubly on said sleeve,the screw being entirely inclosed by the sleeve and the nut from end toend of the hub and so that the screw cannot contact with or wear againstthe hub.

2. The combination with a chair-hub having a smooth vertical bore and amedially-disposed annular shoulder therein, of a sleeve substantially aslong as and fitted and revoluble in said hub on said annular shouldertherein, exterior annular bearing-surfaces on the sleeve adapted to bearagainst the hub near the top and the bottom of the hub and above andbelow the annular shoulder on the sleeve whereby it is supported in thehub, a screw fitted loosely in the sleeve and held to rotationtherewith, and a nut on the screw supported 011 the sleeve Thecombination with a chair-hub having a smooth vertical bore and amedially-disposed annular shoulder therein, of a sleeve fitted looselyin said hub and supported revolubly on said annular shoulder therein,said sleeve being provided longitudinally thereof with agroove orgrooves in its inner surface, a screw fitted loosely in said sleeve andprovided with a laterally-projecting pin or pins entering said groove orgrooves and holding the sleeve to rotation with the screw, and a nutturning on the screw and supported on the sleeve.

4-. The combination with a chair-hub having a smooth vertical bore and amedially-dis.- posed annular shoulder therein, of a sleeve substantiallyas long as and fitted and revoluble in the hub on said annular shouldertherein, a screw fitted loosely in and revoluble with the sleeve butmovable endwise therein, a nut turning on the screw and supportedrevolubly on the sleeve within and at a distance from and constantly outof contact with the wall of the bore of the hub, and a holding screwturning through the hub above the top of the sleeve and into an annulargroove in said nut.

In testimony whereof I afilx my signature in presence of two witnesses.

JULIUS M. GERMANSON.

Witnesses:

A. L. MonsELL, ANNA V. FAUST.

